Device for setting sights on small rifles



Jan. 22, 1963 G. L. COOPER DEVICE FOR SETTING SIGHTS ON SMALL RIFLES 2 Sheets-Sheet 1 Filed June 8, 1959 INVENTOR Glenn L. Cooper ATTORNEY Jan. 22, 1963 G. L. COOPER 3,074,172

DEVICE FOR SETTING SIGHTS ON SMALL RIFLES Filed June 8, 1959 2 Sheets-Sheet 2 INVENTOR. 49 BY Glenn L. Cooper United States Patent Cfiice 3,fl74,l72 Patented Jan. 22, 1963 3,074,372 DEVICE FGR SE'ETENG Til GHT N SMALL Glenn 1.. Cooper, 813 S Loyola, Tucson, Arie.

Filed dune 8, 1959, Ser. No. 818,967 14 Claims. (U. 33-46) My invention relates to devices for setting rifle sights and is a continuation in part of my abandoned application Serial No. 442,579, filed July 12, 1954. The invention relates more specifically to a simple, inexpensive and easily fabricated device for setting telescopic sights on relatively small bore rifles such as Sporting rifles, although it may have other utility as will be apparent from the de scription.

Relatively small bore shoulder rifles are commonly sold with open types of sights forming an inte ral part of the rifle as it leaves the arms factory. Sooner or later almost every owner of a sporting rifle will decide to equip it with a telescopic sight, and it is not uncommon to transfer a telescopic sight from one rifle to another. Periodically, also, a desire is felt to check the setting of telescopic sights. In any one of these instances, as well as in other instances where the accuracy of sights may be involved, it is usually necessary to employ the services of a gunsmith; and even then the owner must shoot in the sight by firing repeated test rounds under controlled conditions. While gunsmiths have developed various methods for bore sighting rifles, particularly bolt action rifles, the ordinary person owning several rifles generally i not cquainted with such methods and does not have the facilities to use them. The methods employed by gunsmiths, moreover, are relatively tedious and frequently do not result in obtaining extreme accuracy unless the gunsmith happens to be particularly skilled. Moreover, the user of the sight has no way of checking the accuracy of the setting of a telescopic sight, even though he shoots many trial rounds for test purposes.

The principal object of my invention is the provision of an inexpensive and simple method for setting rifle sights very accurately. 7

Another object is the provision of a simple, inexpensive device which may be used either to initially set the rifle sights or to check them at any time when there is reason to believe that loss of adjustment may have occurred.

Still another object of my invention is the provision of a simple, inexpensive device for bore sighting relatively small shoulder rifles adapted to be used on a relatively large number of different types and bores of rifles.

Other objects and specific features of the invention will be apparent from the following detailed description taken with the accompanying drawings, wherein:

FIG. 1 is a perspective view showing one embodiment of the device of my invention;

PEG. 2 is an elevational view, though somewhat reduced in size as contrasted with FIG. 1, and showing in dotted lines the breech portion of a rifle with part of the stock and with a telescopic sight mounted in position;

FIG. 3 is a composite view showing a rifle supported in a suitable manner for checking its sights, and indicating the relative'position of a target;

FIG. 4 is a sectional view through the target sighting device, the view being full scale;

FIG. 5 is an enlarged, transverse sectional view taken on the line 5-5 of FIG. 4 looking in the direction of the arrows but with the target dotted into position to indicate the manner in which the device is used;

FIG. 6 is a perspective view partly broken away, showing a modification; w

FIG. 7 is a side elevational view showing a modified form of my invention which is particularly adapted for use on a relatively large number of difierent types of rifles;

FIG. 8 is a sectional view taken through the shell portion of the device shown in FIG. 7;

FIG. 9 is an elevational view of a plug or reticule carrying cross hairs and insertable into the shell comprising FIG. 8;

FIG. 10 is a fragmentary sectional view taken on the line Ill-10 of FIG. 7 showing the reticule held in posi* tion by a retaining ring;

FIG. 11 is an elevational view of a mirror-retaining and positioning bracket;

FIG. 12 is an elevational view looking from the right hand end of FIG. 11;

PEG. 13 is a fragmentary elevational view showing the position of the mirror on the mirror bracket, the mirror also being shown in FIG. 7;

FIG. 14 shows the position of the shell in a rifle having a relatively small diameter chamber;

F116. 15 is a similar view showing the position which the shell may have in a relatively large diameter cham her; and

FIG. 16 shows the manner in which an adapter may be used on large rifle chambers when the shell forming a part of the available bore sighting device is too small to be supported snugly in such chamber.

The embodiment of my invention illustrated in FIGS. 1 through 6 comprises a shell 19, which may be an empty cartridge case originally produced at the factory to fit the particular rifle, the sights of which are to be checked. The shell 14 has a'usual form of base 11 from which the usual primer cap has been removed to leave a primer hole 12 aligned with the axis of the cartridge case. In producing the device of my invention the hole 12, if necessary, may be enlarged somewhat to provide for the passage of more light than would normally pass through the relatively smaller primer opening. The case also has the usual shoulder 13 found in many types of rifles, and the usual neck 14 in which the projectile (not shown) is supported. Secured to the rear portion of the base 11 is an arm 16 having a portion 17, to the face of which a relatively small mirror 18 is adhesively secured. Inserted and secured at right angles to each other in the neck portion 14 are a pair of crossed wires 19 and 21, these wires being so inserted in suitably drilled holes in the neck that they cross each other substantially along the center line or axis of the cartridge case. They may be held in position in any of several different ways, as by means of a trace of solder which will fill the space between the hole drilled in the neck and the contiguous portion of the wire, all residue of solder being wiped off so that the cartridge case will fit into the rifle for which it was intended as easily as if it had not been modified in any way.

While the cartridge case shown is common in shape to those found in several modern hunting rifles, it will be understood that the cartridge case may vary in many ways. All that is necessary for the proper functioning of the device is that the cross wires be supported suitably in the general. neck portion of the cartridge case, that an axial opening be provided in the base of the cartridge case, and that a mirror be suitably mounted at the rear of the base to perform its intended function.

The sight setting device of my invention has its greatest utility with a rifle of the general type shown in FIG. 2 in which a receiver is opened by means of suitable mechanism such as a lever 22, leaving just sufficient space in the shell ejector opening in the receiver for the insertion of the device and leaving the mirror in position as shown in the drawings'where it can'be seen readily when looking directly into the shell ejector opening in the receiver with the line of sight generally perpendicular to the axis of the rifle bore.

In connection with the placement of the mirror, it is suggested that the mirror be placed at an angle of about 45 to the axis of the cartridge case. This figure is used merely to indicate the function, it being obvious that the angle at which the mirror is set is not critical. As an example, in one type of rifle with which I have worked the receiver is so dimensioned that the best results are obtained with the plane of the mirror at about 60 to the cartridge axis and, of course, to the bore of the rifle when the cartridge is mounted in position. This means that the mirror will then be at approximately 30 to the line of sight of the user of the device. In general, the angle between the mirror and rifle axis may be suitably between about 30 and about 60".

In this connection I Wish to point out that I preferably employ a malleable material such as brass or bronze for the arm 16 and the mirror support 17; so that if it is necessary for any reason to change the angle of the mirror slightly, as for example if the mirror should be distorted by accidentally trying to return the action to flriing position when the device is in position in the barrel, it is possible with the hands to reshape the arm to place the mirror exactly at the angle desired.

In the illustrative arrangement of FIGS. 2 and 3, the telescopic sight 23 has a rear mount 24 and a front mount 26 which also provides a light shield over the front lens (not shown). Indicated also is an adjusting member 27 to raise or lower the cross hairs for distance adjustment, and at 28 a member for adjusting for windage.

In FIG. 3 the rifle is shown supported rigidly in a suitable vise 29; and a target 39 with a bulls-eye 32 and circle 31 is shown at a suitable distance indicated as 100 feet from the muzzle of the rifle.

Assuming that the telescopic sight 23 was to be mounted on the rifle shown, the sighting device of my invention would be inserted in the breech through the shell ejector opening in the receiver in the manner shown in FIG. 2 with the rifle fixed as by means of a vise with the muzzle pointed directly at the bulls-eye 32 on the target 30. Adjustment should be made so that the bullseye 32 will be seen in the mirror in the position indicated in FIG. 5. By selecting a suitable distance and a bullseye of suitable size, a result can be obtained in which small, equal-area portions of the bulls-eye appear in each quadrant formed by the crossed wires or hairs. With the rifle then held in position and the bulls-eye of the target shown as indicated in FIG. 5, the telescopic sight is mounted and adjusted by means of its mounts until the target appears exactly in the same position with respect to the cross hairs in the telescopic sight. This of course represents the zero setting of the telescopic sight and the adjusting members 27 and 28 should be properly positioned, as will be explained hereinbelow. With the telescopic sight in this position, it is mounted firmly on the rifle and, if a final check shows that in both the mirror and the telescopic sight the target appears in exactly the same way (making, of course, suitable allowance for the enlargement of the particular telescopic sight used), the final tightening can be applied to the telescopic sight and the sighting device removed with the assurance that perfect adjustment has been obtained. With this arrangement it is absolutely unnecessary to do any test firing to be assured of accurate results.

The windage adjustment 28 should of course be set to zero when the telescopic sight is mounted in position, just as it would be done in any mounting method used. The trajectory or range or distance adjustment 27 may be set in various ways, depending upon the rifle used and the wishes of the user. Every rifle will project a bullet a known distance, with no appreciable drop from a straight or line-of-sight path. It is of course obvious that the best results are obtained with my invention if the target 30 is set at a short enough distance that the bullet or projectile will not start to drop appreciably,

but any distance within the limits of the particular rifles power to carry a bullet can be used for sighting-in purposes if allowance is made for the known ballistics path of the projectile.

As a specific example, 250-257 and other such rifles are supposed to project a bullet on substantially a straight line for about yards, so that the total drop in such distance is small enough to be disregarded. Thus, assuming that one were installing a telescopic sight on such a rifle, the target 30 could be placed 10 to 100 yards or thereabouts from the muzzle of the rifle. Assuming also that the owner of the rifle wanted his sights zeroed-in at 300 yards, the adjustment 27 could be moved to lower the cross hairs a distance equivalent trigonometrically to the drop which would occur at 300 yards. This would call for an adjustment of a certain number of inches, the exact amount to be determined by reference to ballistic tables which are available for all rifles. It is obvious that by first adjusting the cross hairs of the telescopic sight to lower than a suitable amount and then sighting-in on the target 30 when held at 100 yards in the manner described hereinabove and tightening the telescopic sight up at this adjustment, the rifle would then shoot high at 100 yards when the adjustment 27 was brought back to zero position. If, however, one were to sight on an object at 300 yards with the sight adjustment 2.7 at zero, he should hit his targeteverything else being properly carried outbecause at zero adjustment an allowance will already have been made in the telescopic sight adjustment for the drop of the projectiles path at the longer range. Thus it will be seen that without any actual shooting-in it is possible to zero the sights at any distance selected by the owner of the rifle.

FIG. 6 shows a modification, and for convenience I have indicated the parts identical with those in FIG. 4 by the same reference characters but with the prefix 1 to indicate modification. In this form of the invention I utilize a clear plastic plug in the form of a lens 133 which is large enough to fit into the neck of the eartridge case, into which plastic lens cross hairs 134 have been molded by methods known in the industry. While the separate wires 19 and 21 are shown in the first embodiment to facilitate an understanding of the invention, I have found in actual practice that several advantages flow from the use of the clear plastic lens 133. There is, of course, an advantage in the use of the wires in that a small number of devices may be made economically in the ordinary workshop; but for the most part, the advantage of the separate wires begins to disappear when the number to be fabricated increases. One advantage is that the plastic lens can be made to fit snugly into the neck of the cartridge case, and all that is necessary is merely to shove it into place and perfect alignment will result. Another advantage is that the cross hairs can be made somewhat smaller and can be slightly forward, thereby contributing slightly to the accuracies involved. When using separate cross wires I prefer to mount them back away from the edge of the neck so that there is less possibility of injuring or bending them.

There is still another advantage to the use of the plastic lens, and this advantage is tied up with the need at times to adapt the invention for use with rifles of many different types. It is of course possible to separately fabricate a shell to fit a particular rifles breech and it is also possible to design and build an adjustable support which will fit a large number of the rifle barrels and hold a mirror and cross hairs in the desired relationship pointed out hereinabove. Such approaches to the design and fabrication of the device of my invention, however, are not economically sound, there being a definite advantage in several ways in using for the purpose a cartridge case which has already been carefully and accurately designed and fabricated to fit the breech end of the bore.

I have found that a relatively small number of lenses savages 133 may be made to fit the necks of all common cartridge cases with which the ordinary gunsmith may be concerned. By providing a gunsmith with a suitable number of lenses 133, he can mount them in the necks of cartridge cases as the demand arises; and the arm supporting the mirror may be easily applied in position by soldering and as easily removed if there is no further need for using the particular device so made. It is also possible to form any one of several simple, quick conmeet and disconnect structures between the arm 16 and the cartridge case. Generally speaking, however, the device of my invention is so relatively inexpensive that a gunsrnith may readily carry separate devices for several different types of rifles, and the individual rifle owner may have one to fit his own rifle so that he may personally check in his own sights for his own satisfaction.

Concerning the angle of the mirror further, it is desirable that its plane be substantially vertical when the rifle is horizontal and in a proper shooting position so that the line of sight of the observer of the image on the mirror is substantially horizontal. It is also advisable that the mirror be at such an angle to the rifies axis (30 to 60 being suggested) that a full, unobstructed view of the mirror is possible to show a truly circular bulls-eye when the sight is directed into the shell ejector opening of the receiver in a normal manner.

In the embodiment of the invention shown in FIGS. 7-16 I employ a relatively thick-walled shell 36 having a tapered exterior surface 37 and a uniform tubular bore 38 which may be normally approximately in diameter or at least large enough to pass the image of barrels with which it is intended to be used. The taper of the exterior wall 37 is indicated in the drawings as between about to about on each side (or a total of about .025) where the overall length is approximately 1 /2. This taper corresponds closely enough to the taper provided in the chambers of small 'oore r :63 that it will always seat itself firmly in the breech without wobbling within the range of sizes it is adapted to accommodate.

At one end of the shell 36 is an annular projection 39 leaving an exterior end shoulder it against which a bracket 43 with a mirror support 2-3 is adapted to engage. As shown particularly in FIGS. 11 and 12, the supporting or attaching bracket d3 has a fiat body portion 42 generally in alignment with the outer edge of the shell 36. The bracket 43 has an opening :6 (FIG. 12) which engages snugly around the annular projection 39 on the shell as and permits one face of the attaching bracket 43 to lie flat against the shoulder 41. To assure adequate rigidity between the attaching bracket and the body portion of the support, relatively small beads 4'7 are formed on exterior edges in the process of stamping and shaping the mirror-supporting bracket 43. At the end of the body portion 44 opposite to the attaching bracket 43 is a mirror-supporting bracket extension 48 preferably placed at an angle of 45 to the axis of the shell member 36. A mirror as is adequately secured as by means of a suitable adhesive to the bracket extension 4%, as indicated in FEGS. 7 and 13. To protect the mirror and avoid any possibility of its breaking, tabs 51 are folded up from the material comprising th supporting bracket and lie on three sides of the mirror substantially at right angles to the mirror surface, the fourth side of the mirror being protected adequately by the body portion of the bracket itself.

At the forward end of the shell 36 (viz, opposite to the end to which the mirror is attached) an end opening 52 is provided slightly larger than the diameter of the tubular bore 32; forming a shoulder 53 against which a plastic or glass reticule is adapted to be held by means of a retaining ring which is expanded into a still larger diameter portion 37. While many different retaining means may be employed, 1 have obtained exceptionally good results by the use or" a commercial product known in the trade as a Truarc retaining ring. By further reference 6 to FIGS. 8 and 10 it will be noted that there is a portion of the opening 52 immediately adjacent to the shoulder 53 which is of slightly greater diameter than the remaining portion of the opening. From a machining standpoint this provides improved means for assuring provision of a shoulder 53 lying in a plane directly at right angles to the bore of the shell 36 and proper operation of the machining too-l without in any way afiecting the surface of the opening which the reticule 54 engages. In this manner the reticule will always be retained firmly and in lane exactly at right angles with the bore of the shell As shown in FIG. 9, the reticule 54 has cross hairs 58 at right angles to each other and with the point of their intersection at the right center of the reticule. I have not shown these cross hairs in FIG. 10 because they are very small in diameter and to attempt to show them in FIG. 10 is confusing. At a relatively very low price I have bee able to purchase reticules formed of clear plastic with very fine and very clear cross hairs and having more than adequate accuracy. Preferably, however, I have used a clear glass reticule with the same type of accuracy of cross hairs and overall dimensions, also at a low price and with the advantages resulting from the use of such a product. I am not fully acquainted with the manner in which such products are made with a high degree of accuracy and at a low cost, but they are available for purchase on the open market.

I have been able to make the shell 36 relatively very inexpensively when following the design shown by producing the same on an automatic screw machine, small turret lath or other type of commonly available machine tool using relatively inexpensive alloys such as those known in the trade as screw machine stock. By suitable tooling, very great accuracy is maintained automatically with the exception of the outside taper on the shell which I produce as a final piece part operation on a centerless grinder. In this way a very high finish is provided on the completed part. The mirror-supporting bracket 4-3 is blanked and shaped in accordance with common practices, and the attaching bracket 42 is secured to the shoulder 41 and around the annular projection 39 of the shell 35 preferably by means of silver solder.

The completed device is employed in the same general manner as the embodiment shown in FIGS. 1-5 inclusive, with the further added advantage that, suitably designed, it can be used for bore sighting a relatively large number of lever and slide action loading, side ejectin relatively small bore rifles. Using the design shown with the taper indicated in PEG. 8, in which the overall length of the shell is 1 /2" and its major diameter .466", it can be used on almost all rifles having the following bores: .220, .243, .244, .250, .257, .270, .300 (including 30.06), .351, the .35 Remington, and foreign rifles having a bore of 6.5, 7.62, and 8 mms.

While the finish applied to the device of my invention may vary, I have obtained very good results by using a completely black finish, preferably a non-reflective black, throughout except, of course, for the reticule and the mirror. While many finishes may be used, I have had very good results with a finishing process known in the art as Pentrate. The finish is preferably applied after the assembly of the shell 36 and mirror-supporting bracket 43, but before the mirror and the reticule are placed in position. The black, non-reflective finish prevents stray refiections which would interfere with accurate use of the device. I wish to note also that when the device is used for inspecting a gun barrel for flaws in the manner described hcreinbelow, the cross hairs seem to disappear when the eye is held relatively close to the mirror.

Those skilled in the art will understand that the breech of a rifie is always larger than the bore of the barrel, and is always slightly tapered to permit easy extraction of the cartridge case after firing. The diameter of the breech does not have a fixed relationship to the bore or barrel diameter, as a rifle with a relatively small bore may have a large breech so that the cartridge can carry more powder and thus propel the projectile at a higher speed. This is particularly true of such rifles as the .250, .257, and the .220 Swift. Actually I have found that for the calibres mentioned, the disclosed shell will fit all guns except for about one-half of the .250s and the .257s. Also since the tapers of gun chambers are relatively uniform, a shell tapered as disclosed will engage a sufiicient surface within the breech to hold the shell firmly in position with its axis aligned with the axis of the gun barrel.

In connection with the universality of use of the device of my invention, except for certain rare instances, it should be borne in mind that breech openings of gun barrels are not all the same length; and in designing the shell 36, this fact must be kept in mind. If the shell should engage the shoulder at the end of the breech and just short of the rifle bore before it became firmly seated 'Within the breech, it could not be used successfully on such a gun barrel. I have accordingly indicated in FIGS. '14 and two illustrative positions which the shell 36 might assume in two different gun barrels. In FIG. 14 the shell 36 projects only part way into the breech 61,

leaving a substantial portion of its length protruding.

Nevertheless, and even though only a part of the breech 61 is engaged, the shell 36 will be held firmly in position. In FIG. 15 the breech 161 is smaller and the shell 36 is substantially completely retained within the breech, projecting almost to the shoulder in the end thereof. In examining FIGS. 14 and 15 it should be kept in mind that the rifle breeches and bores illustrated are not meant to conform to any particular known firearm, the dimensions being arbitrarily selected for purposes of illustration.

Since for all practical purposes it is impossible to pro duce a shell 36 which can be used to bore sight all existing sporting type rifles, a series of such devices may be produced so that among them means will be made available for bore sighting any existing or future designed relatively small bore, breech loading rifle. I have found, however, that there are only two gun series of small bore rifles which the disclosed shell will not fit; namely, the Magnum series, and the .348 series. For such use I may employ the identical shell shown in the last described embodiment and provide therewith a tapered sleeve 62 as shown in FIG. 16. Such a sleeve will have an inside tapered diameter to fit snugly against the exterior of the shell 36, and an outside tapered surface for fitting the breech of the particular gun to be bore sighted. The sleeve 62 may be machined and ground accurately in the same general manner used in producing the shell 36 at relatively little expense.

While the principal function of my invention is to provide at low expense to any gun owner a device which not only permits him to set his sights but also to check them from time to time, it also has other adVantagesprincipally to permit frequent and thorough inspection of a rifle bore throughout its length and to detect such conditions as pitted lands and grooves, flaws, rust conditions, corrosion and the like. It also shows a bent or sprung barrel immediately, a much more frequent condition than is generally realized. A bent barrel will show an oval pattern in the mirror, the flat position of the oval indicating the plane in which the bend occurs.

I have described my invention in detail so that those skilled in the art may understand the best manner of producing and using the same. I do not Wish to limit the scope of my invention, however, because of any of the details so described, the scope of the invention being defined only in the claims.

I claim:

1. A device for setting a sight on a rifle comprising a cartridge case for such rifle with its primer cap removed to form a center hole in the cartridge case base, an arm of malleable material projecting rearwardly from the base, a mirror carried by the arm in alignment with the cartridge case axis and at an angle thereto, and wires projecting at right angles to each other through the cartridge case neck and crossing at the cartridge case axis, the said mirror angle being such that when the cartridge case is inserted in the breech end of the rifle barrel, sighting into the shell ejector opening in the receiver at substantially right angles to the rifle barrels bore axis shows an image along the said bore axis with the crossed wires on the cartridge case aligned with the line of fire of the said rifle barrel.

2. A device for setting sights on relatively small breech loading rifles comprising a shell having an axial tubular opening and tapered exterior circular coaxial surface, means supporting cross hairs Within said shell at its forward smaller diameter end with the point of their intersection at the longitudinal axis of the said shell, an arm secured to the shell and projecting rearwardly therefrom, a mirror carried by the arm, said arm supporting said mirror within the shell ejector opening in the receiver and facing outwardly therefrom and at an angle of about 45 to the rifle axis bore when the said shell is lodged in the breech thereof, so that the bore of the barrel of such rifle may be sighted by looking directly into the said shell ejector opening, said arm and mirror being dimensioned to pass through a breech opening as the shell is inserted into the said chamber.

3. A device as defined in claim 2 wherein said shell has a taper and exterior dimension to permit its fitting a relatively large number of rifle barrels.

4. A device as defined in claim 2 wherein said barrel has relatively thicker side walls than a usual cartridge case to provide relatively greater rigidity and stability, and wherein the axial tubular opening therein is of substantially uniform diameter.

5. A device as defined in claim 2 wherein said barrel has relatively thicker side walls than a usual cartridge case to provide relatively greater rigidity and stability, and wherein the axial tubular opening therein is of substantially uniform diameter except for a relatively larger diameter portion at its forward end, and wherein said cross hairs are molded in a transparent reticule held in said larger diameter portion.

6. A device for setting gun sights on relatively small bore, breech loading rifles comprising a shell in the shape of a cartridge case having a base, generally tubular side walls and normally open neck, said base having a central opening therein, means forming two lines crossed at the axis of said shell, an arm projecting rearwardly from the base, and a mirror supported by said arm in alignment with the shell axis but at an angle thereto at a position in the breech for sighting down the rifle barrel, said arm and mirror being dimensioned to fit Within the shell ejector opening of the receiver when the shell of the sighting device is inserted into the breech.

7. A device for setting sights on relatively small bore, breech loading rifles comprising a shell adapted to be supported in a breech end of a rifle in alignment with its bore axis, crossed hairs carried by a forward portion of said shell in alignment with said bore axis, a mirror, and means on the shell supporting the mirror in the breech at an angle to the said bore and in alignment with said cross hairs, said mirror and support means projecting rearwardly from the shell and being dimensioned to pass through a shell ejector opening in the receiver as the shell is inserted into the rifle breech.

8. A device for setting sights on relatively small bore, breech loading rifles which comprises a relatively thick walled shell having a tubular axial opening of generally uniform cross section and generally tubular exterior surfaces tapering slightly toward its forward end, a central axial annular projection at the maximum diameter end of the shell leaving an annular flat shoulder, a supporting bracket having a body portion generally aligned with the exterior surface of the shell, an attaching projection at right angles with the body portion and having a central opening to receive said annular shell projection and lying flat against said shoulder, a mirror-supporting projection facing inwardly from said body portion at an angle of about 60, said mirror-supporting projection having a mirror secured thereto, and mirror-supporting tabs projecting up around the mirror to protect the same, the forward end of said tubular opening in the shell being provided With a relatively larger diameter portion forming an annular shoulder, a transparent reticule engaging said shoulder and fitting snugly within said larger diameter portion, said reticule having cross hairs at right angles to each other and intersecting along the axis of said tubular opening, and a reticule-retaining ring expanded into a narrow still greater diameter portion of said tubular opening, said supporting bracket and mirror being dimensioned to pass a shell ejector opening in a receiver when the shell of the device is inserted into the breech of the rifle.

9. A device for setting sights on relatively small bore, breech loading rifles comprising a tubular shell with relatively thick side walls, an exterior taper of about .025 inch and uniform diameter bore, a supporting bracket attached to that end of the shell having the larger diameter, a mirror supported on said bracket at approximately 45 angle to said shell bore, in a position and of a dimension to be supported within the receiver of a rifle when the shell of the device is inserted into said rifle breech in alignment with the bore axis, and a reticule secured within a forward enlarged portion of the shell bore, said reticule having a pair of right angle cross hairs with their point of intersection along said bore axis.

10. A device for setting a sight on a rifle comprising a cartridge case for such rifle with its primer cap removed to form a center hole in the cartridge case base, an arm or malleable material projecting rearwardly from the base, a mirror carried by the arm in alignment with the cartridge case axis and at an angle thereto, and wires projecting at right angles to each other through the cartridge case neck and crossing at the cartridge case axis, said arm and mirror dimensioned to pass through a shell ejector opening of a rifle receiver and be supported within said receiver when the said cartridge case of the device is inserted into the rifle breech.

11. A device for setting sights on relatively small breech-loading rifles which comprises a shell having an axial tubular opening and tapered exterior circular coaxial surface, the taper of said exterior surface being of the order of twelve to fourteen thousandths of an inch per lineal inch of surface, a pair of cross wires in the tubular opening co-axial therewith, a mirror and bracket secured to the larger diameter end of said shell, said mirror being at about to the axis of the shell and positioned and dimensioned to be supported in the receiver of a rifle when the shell is lodged in the breech thereof in alignment with the axis of the rifle barrel so that said bore of the rifle may be sighted by looking directly into the breech, said exterior taper of the shell permitting said device to be employed, without adjustment, with a relatively large number of different types of small breech-loading rifles.

12. A sight-setting device as defined in claim 11 wherein said shell has a maximum diameter or" somewhat less than one half inch.

13. A sight-setting device as defined in claim 11 wherein said shell is approximately one and one half inches long and has a maximum diameter of the order of 0.464 to 0.465 inch.

14. The method of setting sights on small bore breechloading rifles which comprises supporting cross hairs in the bore of the rifle barrel in alignment with its axis, sup porting a mirror in the receiver behind the breech at an angle of about 45 to the bore axis so that the bore axis may be sighted by looking directly into the shell ejector opening in the receiver with a line of sight approximately perpendicular to the bore axis, adjusting the bore axis of the rifle on a target while so sighting in the said mirror supported in the breech, and while so holding the rifle adjusting its sights to fall on the same target.

References Cited in the file of this patent UNITED STATES PATENTS 793,131 Henkes June 27, 1905 953,696 Konig Apr. 5, 1910 962,175 Straubel June 21, 1910 2,294,913 Kaufman et al. Sept. 8, 1942 2,773,309 Elliott Dec. 11, 1956 

7. A DEVICE FOR SETTING SIGHTS ON RELATIVELY SMALL BORE, BREECH LOADING RIFLES COMPRISING A SHELL ADAPTED TO BE SUPPORTED IN A BREECH END OF A RIFLE IN ALIGNMENT WITH ITS BORE AXIS, CROSSED HAIRS CARRIED BY A FORWARD PORTION OF SAID SHELL IN ALIGNMENT WITH SAID BORE AXIS, A MIRROR, AND MEANS ON THE SHELL SUPPORTING THE MIRROR IN THE BREECH AT AN ANGLE TO THE SAID BORE AND IN ALIGNMENT WITH SAID CROSS HAIRS, SAID MIRROR AND SUPPORT MEANS PROJECTING REARWARDLY FROM THE SHELL AND BEING DIMENSIONED TO PASS THROUGH A SHELL EJECTOR OPENING IN THE RECEIVER AS THE SHELL IS INSERTED INTO THE RIFLE BREECH. 